Re: [PATCH v2 0/2] xen/x86: implement NMI continuation as softirq

[Jürgen Groß <jgross@xxxxxxxx>]

On 15.10.20 12:49, Roger Pau Monné wrote:
> On Wed, Oct 07, 2020 at 03:30:09PM +0200, Juergen Gross wrote:
> > Move sending of a virq event for oprofile to the local vcpu from NMI
> > to softirq context.
> >
> > This has been tested with a small test patch using the continuation
> > framework of patch 1 for all NMIs and doing a print to console in
> > the continuation handler.
> >
> > Version 1 of this small series was sent to the security list before.
> >
> > Juergen Gross (2):
> >    xen/x86: add nmi continuation framework
> >    xen/oprofile: use set_nmi_continuation() for sending virq to guest
> Apart from the comments in patch 1, I think this is a fine approach if
> it allows us to restore to the previous state of the event lock.
This will not be enough to do that, but it is clearly removing a
potential deadlock.

> I think we should be expecting a v3 with the nmi callback prototype?
And using an IPI instead of a softirq, yes.


Juergen